Different types of music equipment/audio devices frequently use different types of interconnectable male and female connectors of different sizes that are commonly jointly referred to as headphone connectors. Examples thereof are mobile phones and various types of portable AV devices, such as mp3 players, that in most cases are equipped with a 3.5 mm size female connector that is commonly named a minijack or mini socket and that is intended for receiving a corresponding 3.5 mm size male connector that is commonly named a miniplug or minijack plug. On the contrary, professional audio equipment frequently uses a bigger 6.3 mm size female connector, namely a jack/socket also commonly named a ¼ inch jack, a full-size jack or a phono jack that is intended for receiving a corresponding 6.3 mm size male connector/plug. It is often regarded as a problem that such different connector types/sizes are used in various types of audio devices and equipment. It has the effect that users frequently switching between e.g. portable devices and non-portable equipment are required to employ an adapter when connecting accessories, such as headphones thereto. Such adapters are often small in size and are therefore easily misplaced or even lost.